The Case for Going Slow

A recent story in BoatTest:


(I wish I could get the Admiral to agree with this!)

Surprised this article focuses on cost. For distance cruising, a displacement boat will ofren be faster than a planing or semi-planing counterpart. It's a "tortoise vs hare" thing. A 65 foot displacement boat will tick over 200-225 nms per 24 hr period. A planing boat will do that in 14 hours but have to stop for fuel and risk having to time their entrance and exits. Yes, crew gets to rest at dock and perhaps be more selective about weather, but more often than not, there will be no net time savings despite being able to go 2.5x speed of displacement boat. And difference in cost is considerable if that's a concern for the owner.

I once played leapfrog with a 65 foot Azimuth in this very manner when I was delivering a 60 footer. Over the course of a 750 nm delivery, both boats arrived at similar times.

Peter

In the PNW, log avoidance is a big reason to go slow, in addition to the fuel saved.

Concern about cost is relative. I suspect Jeff Bezos doesn't think much about the fuel burn on his yacht. For those of us closer to the opposite end of the economic spectrum it can be a different matter.

My boat burns 1.3 gph at 7 kts. Doubling speed to 14 kts increases consumption to 20 gph - a 15x increase (and 29 gph at 17.7 kts, hopefully to be improved a bit with prop tuning or perhaps a different prop). While the amount of fuel I'm likely to use, even at 20 gph, over the course of the rest of my boating life is a fraction of the original cost of the boat (barring war in the Mideast that skyrockets fuel prices), it's still painful to hand over a credit card to pay that much.

However, at least in my experiences it does make a difference for the kind of boating we've done. The Admiral doesn't like long passages. Her preference is to spend 4-5 hrs/day underway and arrive at the next destination with plenty of time to explore, relax, shop, get a meal, etc. Cruising at 14 vs 7 kts is more than twice the distance - it's a 4-fold increase in the area we can cover in a given day regardless of how many hours spent underway.

My boating has also largely been effectively 'single handing' as the only person on board capable of handling the boat. Especially at my age I get tired after several hours. I also don't want to be underway at night. 24 hr runs are just not going to happen for me (never did). A run such as Cape May NJ to New York Harbor (120-ish nm) is doable in daylight in a single day at 14-15 kts, but not at 7-8 kts.

mvweebles said:

Surprised this article focuses on cost.

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The article does list as #1:

But the article does talk a lot about cost. Our reason for going slow is the same as #1; we consider boating to be sight-seeing. If we needed speed, we would likely drive to the destination. Washington and British Columbia have good ferry systems, so access to the islands or a remote harbor isn't an issue. The majority are accessible by car. Ripping across the Sound to eat lunch and then tearing back just isn't boating for us. Besides, it's cheaper to take the ferry.

Being retired helps. Since we don't stay at marinas, we don't need to get to the marina by 2 p.m. to get a slip or a certain time to guarantee a dinner reservation. We don't need to pull a wake board or throw out any wake at all. 5-7 knots is our comfortable look-around speed.

Last year, we cruised 900 miles. Our overall speed average, including warm-ups, docking, etc., came out as 6.4 knots. That's because we generally time our passages to run with the current. Our wildest hell-for-leather passage was a couple minutes at 11 knots SOG through a tidal rapid. Can't imagine maintaining that insanity. But I do it occasionally to keep fuel down to just over a gallon per hour. So there is also a cost element.

One of the advantages of going slow for sight-seeing is that it is possible to go closer to shore. At <5 knots, I often travel along in 30 feet. At 11 knots, I'd be out in the deep water, maybe a mile offshore. We are very, very fortunate in that the Chiton can't go 11 knots. The perfect trawler.

"Is that a wolf on the shore or a sea lion? Where? Never mind, it's behind us now."

(Hey, where did the smiley face thingies go?)

Mark

I'm a slow cruiser at 6 to 7 knots with the occasional 7 to 8 when sea state is better handled by speed and momentum. Fuel economy, wear and tear reduction, lower noise levels, and cruising comfort are all good benefits to me.

One of the areas that is less enjoyable is opposing tidal currents. Cruising up the Hudson River, Pablo Creek, Chesapeake Bay, and Delaware Bay are all areas where a 6 to 7 knot cruise can have you making 3 to 5 knot ground speeds. My solution is to ride with the current and nap (at anchor) when it's opposing. It makes for some odd departure times, but who wouldn't like cruising at 8 to 9 knots burning 1.2 GPH.

Ted

Good piece. Thanks for posting it.

Its just a hunch, but my guess is the biggest barrier is among those still asking the "what do I want in a boat" question to themselves. They don't know what the experience differences are between slow and fast.

I am a half season into my H38. It was run WOT, or even at fastest continuous speed, exactly once last year, just to do it. The difference in experience confirmed my choice to focus on slow. Shoppers still in the arm chair hunt can't know that.

On a different but related note, there is a major difference in needs between the retired folks and those still working. If working, the important range factor is how far one can go and still be back at the dock Sunday night ready for work Monday. Fast and fuel burn can make a lot of sense for them, in a way that makes less sense for the retired with no calendar pressures. Fast adds a lot of potential weekend destinations to the list.

Pushing 65000 lbs with 450 HP, I can’t comment on planing speeds, however it is always interesting while using Navigation to a destination, how little difference in ETA results from dropping to 7 knots from 8. Arriving at the next anchorage 40 minutes later makes the reduction in noise and fuel burn all the more attractive. But it took me while to figure that out!

Back when I had my express cruiser, I'd fly across the lake every now and then, but it was far more comfortable and enjoyable to cruise at 7 knots, which was mostly how I used it.

Ken E. said:

In the PNW, log avoidance is a big reason to go slow, in addition to the fuel saved.

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I agree and it's the same with crab and lobster pots. Its also less stressful going at displacement speeds plus when you go aground, its usually not as damaging.

mvweebles said:

Surprised this article focuses on cost. For distance cruising, a displacement boat will ofren be faster than a planing or semi-planing counterpart. It's a "tortoise vs hare" thing. A 65 foot displacement boat will tick over 200-225 nms per 24 hr period. A planing boat will do that in 14 hours but have to stop for fuel and risk having to time their entrance and exits. Yes, crew gets to rest at dock and perhaps be more selective about weather, but more often than not, there will be no net time savings despite being able to go 2.5x speed of displacement boat. And difference in cost is considerable if that's a concern for the owner.

I once played leapfrog with a 65 foot Azimuth in this very manner when I was delivering a 60 footer. Over the course of a 750 nm delivery, both boats arrived at similar times.

Peter

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There’s a lot of oranges in this bushel of apples. You’re comparing a 65’ displacement hull to a ?? planing hull traveling at ?? speeds with ?? amount of fuel capacity, ?? amount of horsepower and ?? fuel type. Now, three identical length displacement, semi-displacement and planing hulls all traveling at displacement speeds, same fuel capacity, same horsepower engines, same fuel type(gas vs. diesel), your results won’t vary that much.

mmullins said:

There’s a lot of oranges in this bushel of apples. You’re comparing a 65’ displacement hull to a ?? planing hull traveling at ?? speeds with ?? amount of fuel capacity, ?? amount of horsepower and ?? fuel type. Now, three identical length displacement, semi-displacement and planing hulls all traveling at displacement speeds, same fuel capacity, same horsepower engines, same fuel type(gas vs. diesel), your results won’t vary that much.

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It was approx a 65 footer I'd reckon. Traveled at about 20-25 kts compared to our 9 kts. From experience, he probably burned 60-75 GPH and likely carried around 1300 gals diesel but that's only a guess.

Your statement that same general sized boats traveling same speed but one is displacement and the other is planing is correct for short distances on flat water because the differences do not express themselves drastically. I would guess that at 9 kts, that Azimut burned 10 GPH whereas the Nordhavn I was delivering burned 6 GPH. Small difference over a short distance.

Point being that 20-25 kts took similar amount of time as 9 kts.

Going slow? SLOW?! We went from averaging 5.5 knots in our sailboat to doing 7 all the time in the trawler.

It felt like we went from impulse power to warp speed...

Moonfish is my kinda skipper. Well said! Ben

There is fast and then there is FAST. We were passed coming back from Alaska a couple of years ago by an 88' fast cruiser. On AIS they were averaging 33 knots. From radio reports they did Ketchikan to Port McNeill in one easy day, the next day they were in Astoria. At 7 knots you do 168 miles in 24 hours, but at 33 you do 792. The 7 knot boat doesn't catch up. Also from radio reports, they were burning 150 gal/hr.

DDW said:

There is fast and then there is FAST. We were passed coming back from Alaska a couple of years ago by an 88' fast cruiser. On AIS they were averaging 33 knots. From radio reports they did Ketchikan to Port McNeill in one easy day, the next day they were in Astoria. At 7 knots you do 168 miles in 24 hours, but at 33 you do 792. The 7 knot boat doesn't catch up. Also from radio reports, they were burning 150 gal/hr.

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We had a similar experience last year. We were plodding along at our usual 6.5 kts or so when a 90-ish foot Pershing (or rather, the rooster tail from one) appeared on the horizon far ahead of us. I saw the spray before I saw the boat. It was all of a few minutes before he passed us and disappeared behind us doing 35 kts or so. We're a fast boat compared to many on here (fast cruise is ~17 kts, WOT around 25 kts) but still nothing compared to something like that.

DDW said:

.....At 7 knots you do 168 miles in 24 hours, but at 33 you do 792. The 7 knot boat doesn't catch up. Also from radio reports, they were burning 150 gal/hr.

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On a longer delivery, the 7-kt boat may very well catch up because the large boat cannot carry enough fuel to run WOT for more than a few hundred miles so will have to stop for fuel which often takes several hours plus in/out (more if you have to time tides). For longer deliveries, the larger go-fast boat is either throttled back to an economical speed or, which was the case with the Azimut I encountered, it stops a lot.

Cost aside, for longer deliveries, running fast does not always seem running fast (if that makes sense).

Peter

My previous GB36 could do 13 at wot, my current boat has done 16 at wot. But I will travel at wot to achieve max rated rpm OR in an emergency. The rest of the time I putt at 7-8 with GB and now 7-10 with Bayliner.
AS with all boats they have a sweet spot, not just for getting on the step to plane, but a speed v. rpm efficiency.
By ear if the engine seems to be racing, and reducing 500 rpm makes if sound sweet then that is the speed we are going to go.
I am finding approx 9 at 2100 is that sweet spot. Any more and I have to be in a hurry. And I can go slower if the scenery warrants.

I worked on the Hessen Yacht Octopussy for a few seasons in Med and loved it.
Its amazing how many cool places you can go in a day at 50 knots.

What always strikes us is that we only come across water-moving boats from the Netherlands when we stay in Scandinavia.
One way trip is about 350 miles and you would expect that the number of fast guys from the Netherlands would be present in Scandinavia, but the opposite is true.
The moral of the story, slow boats, big trips/distances, fast boats, small trips/short distances.

Greeting,

Pascal.

The idea that the 7 knot and the 14 knot boat arrive at the same time is not true, unless the 7 knoty boat travels, and has the crew for 24X7 operation.

I generally travel slow because i like the reduced noise, and cost, and werar and tear on my expensive engines.

That said, I have and will continue to use speed to get me in a day what takes two days for the slower boat.

So many what iff's favor the faster boat. OK the weather is going to get snotty day after tomorrow. So... I can pick up the pase anbd make that interesting harbor, or I can gon slow and be stuck for several days in a boring harbor.

Or the time I lefr Morro Bay at first light headed for Santa Barbara. I called the harbormaster who does not take reservations and was told he had two slips available, but by dark they would for sure be full.

So... I got after it, spent some diesel, and was sipping a nice glass of wine in my cockpit when the slower boat was told to anchor out.

Pascall said:

What always strikes us is that we only come across water-moving boats from the Netherlands when we stay in Scandinavia.
One way trip is about 350 miles and you would expect that the number of fast guys from the Netherlands would be present in Scandinavia, but the opposite is true.
The moral of the story, slow boats, big trips/distances, fast boats, small trips/short distances.

Greeting,

Pascal.

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I did about 20 Atlantic crossing at 12-15 knots and don't remember wanting to go any slower. I cant even imagine doing a 45 day crossing. Some times its the journey and sometimes its the destination.

ksanders said:

The idea that the 7 knot and the 14 knot boat arrive at the same time is not true, unless the 7 knoty boat travels, and has the crew for 24X7 operation.

I generally travel slow because i like the reduced noise, and cost, and werar and tear on my expensive engines.

That said, I have and will continue to use speed to get me in a day what takes two days for the slower boat.

So many what iff's favor the faster boat. OK the weather is going to get snotty day after tomorrow. So... I can pick up the pase anbd make that interesting harbor, or I can gon slow and be stuck for several days in a boring harbor.

Or the time I lefr Morro Bay at first light headed for Santa Barbara. I called the harbormaster who does not take reservations and was told he had two slips available, but by dark they would for sure be full.

So... I got after it, spent some diesel, and was sipping a nice glass of wine in my cockpit when the slower boat was told to anchor out.

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On that day it worked out that the fast boat was faster. But Morro Bay cannot be reliably entered in all weather, nor can it be reliably entered at all times of day due to tides/currents and weather. Using the same boat but going slower to extend range and therefore bypass stops like Morro Bay where you can easily get stuck can often be much faster.

Peter

We boat pretty similarly to Kevin's point. Slow most of the time, but there are certain times where going faster provides enough benefit to justify the fuel (cruise speeds are about 6.5 and 17 kts for us). Blasting around on plane all the time doesn't make sense unless it's just for fun (with deep pockets) though.

I've said before, we mostly prefer to run at trawler speeds... even though we can make somewhere up around 30 kts if necessary. (So far, hasn't even been necessary.) And we usually aim to break our trip into 50-70 NM segments... to hold down the fatigue factor.

Our fuel consumption is a bit all over the map at slow speeds, since we're greatly affected by wind and tide/current. Crossing Bogue Sound the other day, against the tide and with some headwind, we were using about 6 GPH (total for both engine) at about 8.5 kts. Yesterday, moving from Oriental to Belhaven and in calmer weather at about 8.5 kts, we were down to 4 GPH, which is usually about as economical as we can get. Not really competitive with true "trawlers" (?) but not all that bad with 1800 hp.

And the Admiral can usually spot Eagles, Osprey, turtles, etc. as we go -- depending on the area -- and the whole trip just seems more enjoyable when we see interesting stuff along the way and we aren't too worn out when we arrive someplace. In time for a pleasant Happy Hour and a decent meal.

Slow -- with a planing hull -- doesn't work in all weather or all sea states, though. I expect tomorrow we'll probably need to get up on plane for a segment just to comfortably deal with the predicted chop...

-Chris

I do understand why some people want to go fast and why others want to go slow.
If you have only 1 week of holiday, chartered a yacht and want to see a couple of places then it makes no sense to go from A to B at 6 kts. In that case you want to cover the distance between the islands (eg here in Greece) in the shortest time possible.
In that case the cost of the extra fuel is outweighed by the benefit of being able to reach (therefore visit) multiple islands.
Same goes if you e.g. only use the boat in the weekend, but still want to be able to get to a nice anchorage.

However, for us, who basically have all the time in the world, we don't have a schedule to keep, so we take it slow. If it takes 3 hours to get somewhere it is fine and if it takes 6 hours to get somewhere it is also fine. We just motor along at 6 - 6.5 kts, enjoy the weather, the scenery, watch dolphins, sail along the coast, take pictures, sit and relax with a cup of coffee, do some maintenance along the way, i.o.w. we enjoy going slow. And since we don't have a schedule there is also no need to burn extra fuel when that is not necessary.

Last year we were in a port on the island of Sifnos, next to us was a 52' Princess. The owner told me it took them about 4 hours to get from Athens to Sifnos and 4 hours back, but doing so he burned roughly 1600 euro worth of fuel each way. It took us about 20 hours to cover the same distance, but along the way we stopped in three different islands (which he just passed by) and we spent about 350 euro in fuel. From our point of view we had a beautiful trip, visited 3 lovely islands and then spent a few days on Sifnos.
I guess that our neighbor was happy that he arrived in 4 hours in Sifnos, so he could sit in the cockpit with a beer and probably think of us poor souls who needed much more time to get to the same place.

Will he ever change ? As long as he can afford the fuel he probably won't.
Will we ever change ? We won't since we are not in a hurry now and will never be in a hurry. The only time I wish we would be able to go a bit faster is when a sudden storm arrives, which we would be able to outrun by going 20 kts. We can never outrun a storm, so we always have to ride it out and that is not really fun.

To me the most compelling case for going slow is the fact that (most of) our boats were designed/intended to go slow.
The development of engines with a much higher power:weight ratio has enabled many to surpass pure-displacement speed, but that alone doesn't make it a good idea.

mvweebles said:

On that day it worked out that the fast boat was faster. But Morro Bay cannot be reliably entered in all weather, nor can it be reliably entered at all times of day due to tides/currents and weather. Using the same boat but going slower to extend range and therefore bypass stops like Morro Bay where you can easily get stuck can often be much faster.

Peter

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Peter I have never wished that I did not have the capability of faster speeds, because that gives me choices that a go slow only boat does not have.

That said I have wished for more fuel capacity which equates to more range. I am separating fuel capacity from engine size choice because...

The small percentage in increased range realized if I changed to for example smaller engines in my boat would not make enough difference to change my cruising habits. But those smaller engines would eliminate my choices.

On the other side I can name quite a few times where my ability to choose my cruising speed enabled me to comfortably, and safely complete my travels.

For example, bar hopping in Oregon and Washington. Being able to choose my speed made for zero night bar crossings.

Choosing my speed allows me to make a new to me anchorage or port in daylight, adding to my safety and mental comfort. This concept played out countless times on the pacific coast.

We all have the boats we have. That said if I was going to choose a new boat, and if my plans did not include passagemaking across oceans, I would choose a boat that allows me to choose and yes pay for with diesel, a wide range of cruising speeds.

Kevin - I did not mean to advocate for slower boats per se, but rather to point out that going slow can often be a faster way to run a boat over a longer distance because the time it takes to take on fuel and navigate entrances. This applies to running a fast boat slow as much as a slow boat run slow (if that makes sense).

Another example - I once delivered a Sunseeker 55-ish footer from Seattle to San Francisco. The owner was aboard and wanted to run at cruising speed. We barely made it to Gray's Harbor on its 700 gals of fuel. It was early April and off season. We got there late Saturday afternoon and the fuel dock didn't open until Monday morning. We ran the rest of the way to San Francisco at 8 knots without stopping (vs running at 25 kts and stopping twice).

In my opinion, distance cruising is done fastest by a slow boat. Or perhaps better said, a boat going slow. Occasionally you can day-trip without paying a time penalty for in/out, but i wouldn't bet on it (and I didn't bet on it even when it wasn't my money paying the fuel bill).

Peter .

@mvweebles
Peter for what it's worth I see the point your are trying to convey.